This invertebrate gripper uses air pressure to grab onto objects. The secret is all in the design. But you don’t have to reinvent the wheel. If you’ve got a 3D printer you can follow this guide to make your own.
The gripper is made of silicone. The trick is in designing an inner structure that deforms in one direction when pressurized. To make one or one hundred, simply download the design files and 3D print a mold. The process from there is much like the silicone band prototyping process we looked at back in March. The two-part silicone is mixed and poured in the mold. You also need to pour some on a flat surface. We were under the impression that uncured silicone would not stick to cured silicone but we were wrong. The two parts are glued together with a fresh batch of the mix. After everything has set up you can pierce the bladder with a hose in order to inject air.
Below you can see the star-shaped version being tested. There’s also a Harvard research video which shows a similar design lifting an egg.
Continue reading “Air-powered gripper design makes them easy to produce”
This jamming gripper design is the simplest we’ve seen so far. It uses a syringe to generate the suction necessary for the orange appendage to grip an object.
As with previous offerings this uses coffee grounds inside of a balloon. When pressed against an object the grounds flow around it. When a vacuum is applied to the balloon those grounds are locked in place, jamming themselves around the item for a firm grip. About a year ago we saw a hardware-store grade design which used a vacuum pump for suction and a shower head as the gripper body. This time around the plastic syringe serves as both.
The plastic tip was cut away and the resulting hole covered with a cloth to keep the coffee in place. After installing the coffee-filled balloon the grip can be operated by pulling the plunger to lock the grounds in place. It’s not going to be as easy to automate as a pump-based rig. But if you just want to toy with the concept this is the way to go.
Continue reading “Dead simple jamming gripper design”
This is the simplest version of a jamming gripper that we’ve seen yet. The only component that might not be readily available is the pump in the upper left, but the rest is all hardware or grocery store stuff. It’s based on the concept we saw from a research video where the air in a bladder full of coffee grounds is removed to grip an item. In this case the bladder is a party balloon which is held in place by parts from a cheap shower head. A theaded-to-barbed right angle connector makes it easy to connect the vinyl tubing up to the pump.
The video after the break shows that this works quite well for small items. But we see a lot of downward force is exerted to firmly embed them in the grounds. We’re not sure if this is par for the course, or if it would work a bit better if more air were in the bladder initially. This other jamming gripper build uses a servo to release pressure from the system, and we think that might be of help here too.
Continue reading “Jamming gripper that’s super easy to build”
Watch out Spidey, there’s a new wall climber in town!
Researchers [Matthew Journee, XiaoQi Chen, James Robertson, Mark Jermy, and Mathieu Sellier] recently unveiled their wall climbing wonder bot at the 2011 IEEE International Conference on Robotics and Automation. Like most other wall climbing bots, theirs operates on the Bernoulli principle to keep it stuck to the surface, but that’s where the similarities end.
Unlike other Bernoulli-based climbers, this robot’s gripper never actually touches the surface it is climbing. The researchers were able to accomplish this feat by designing a specialized gripper which forces air through a 25 μm gap, creating a very powerful low pressure vortex. The gripper’s design compresses the air by shape alone, causing the air flow to reach speeds of Mach 3, without relying on powerful pumps or increased air volume.
The researchers state that their supersonic gripper can support about five times the weight of a conventional Bernoulli gripper, and as you can see in the video below it also has no problem climbing a wide variety of surfaces.
Window-washing Roomba, here we come!
Continue reading “Wall climbing robot uses supersonic grippers”
Here’s an inexpensive way to build your own jamming gripper. [Steve Norris] combined a robot arm with a few inexpensive items to achieve similar results as the original. Much like the last DIY version he started with a balloon and some coffee grounds, but instead of using his own body as a vacuum pump he sourced a Reynolds Handi-Vac, an inexpensive food vacuum sealer. It connects to the balloon using some plastic tubing, and sucks all of the air out, locking the coffee grounds around an object for a firm grip. The video after the break even shows the gripper picking up two aspirin. At first we thought a servo motor was being used to seal off the tube once the air had been pumped out. Instead, it is covering a hole in the tubing, which breaks the vacuum when it’s time to let go of an object.
Continue reading “Jamming gripper completes robot drug dealer”